EFFECTS OF MEMBRANE FATTY-ACIDS ON THERMAL AND OXIDATIVE INJURY IN THE HUMAN PREMONOCYTIC LINE U937

Heat shock (HS) proteins (HSP) function as molecular chaperones and pr otect cells from thermal and oxidative injury. The signals leading to HSP synthesis, i.e. the ''cellular thermometer(s),'' are still a matte r of debate. In the human premonocytic line U937, we investigated the effects of specific modification of membrane fatty acid (FA) compositi on by incubation with various saturated and unsaturated fatty acids (U FA) on the HS response and on hydrogen peroxide (H2O2)-induced cell de ath. FA readily incorporated into U937 cell membranes. UFA did not mod ulate the HS response but potentiated H2O2-mediated damage, while pre- exposure to HS protected the UFA-treated cells from this increased H2O 2 toxicity. (C) 1997 Elsevier Science Inc.